I. Technical Field
The present invention relates to a glass ribbon used for a glass substrate of flat panel displays, solar cells, or the like, spacers, partition walls, insulators, or the like, and a method of producing the glass ribbon.
II. Description of the Related Art
The potential of the so-called ultrathin sheet glass having a thickness of 200 μm or less has been attracting attention (see JP 2008-133174). The ultra-thinning of glass can impart flexibility to the glass. In recent years, there has been such a tendency that the impartment of flexibility to assorted electronic devices has been desired. For example, organic EL displays have been requested not only to be easily conveyable by folding or winding but also to be usable for curved surfaces as well as for flat surfaces. In addition, if solar cells or organic EL illumination can be formed on the surfaces of substances having curved surfaces such as the body surfaces of automobiles, and the roofs, columns, and external walls of architectures, their applications will expand. Further, the ultrathin sheet glass has been expected to find applications in spacers as well, and hence a more thin glass for a spacer has been expected in order to form a more thin space. In addition to the foregoing, the ultrathin sheet glass has been expected to find use in, for example, plasma displays, capacitors, and the partition walls of fuel cells and the like. Accordingly, the ultrathin sheet glass has been expected to find use in assorted applications.
As an attempt besides thinning, an improvement in accuracy of side surfaces has been proposed in order to impart flexibility to thin sheet glass (see JP 2007-197280 A). JP 2007-197280 A below describes a thin sheet glass whose side surface has a surface roughness of 0.2 μm or less. The thin sheet glass described in the document hardly fractures even when a force is applied in a torsional direction, and therefore has a high reliability for a more flexibility.